Conventional one-piece ostomy appliances, and the pouch components of two-piece adhesively-coupled appliances, generally consist of collection pouches equipped with adhesive faceplates of various shapes for adhering the appliances to the peristomal skin surfaces of patients or to the attachment surfaces of mounting rings adhesively secured to such peristomal surfaces. Most commonly, the faceplates have outer margins that are either generally round or square (with rounded corners) as shown, for example, in U.S. Pat. Nos. 5,403,299 and 4,213,458, although faceplates having other outlines are also known (see, for example, U.S. Pat. No. 5,811,116). Regardless of its shape, such a faceplate essentially consists of an adhesive layer, preferably of a hydrocolloid-containing adhesive capable of absorbing moisture and having both wet and dry tack, and a backing layer of polymeric film or fabric covering the backside (pouchside) surface of the adhesive layer and securing the faceplate and pouch together about the stoma-receiving openings of the respective parts. In addition, a typical pouch faceplate assembly is supplied to the user with a removable release sheet that covers the bodyside surface of the faceplate's adhesive layer. To facilitate removal of the release sheet at the time of application, such a sheet is commonly provided with a tab portion that projects away from the periphery of the adhesive layer. In addition, the backing layer may also be provided with an outwardly projecting tab portion to assist a user in peeling the faceplate away from the skin (or from the attachment surface of a mounting ring) when removal of an appliance is desired (see U.S. Pat. Nos. 5,578,023 and 5,607,413).
Where provided, such pull tabs almost always project upwardly, that is, towards the upper ends of the pouches, to render them more readily accessible in use, but such a location has offsetting disadvantages. Because of manufacturing requirements, the perimeter of a faceplate (including its tab portion) must necessarily be spaced inwardly from the periphery of the pouch on which the faceplate is mounted, with the result that a faceplate having upwardly protruding tabs must be located lower along the pouch wall than if such tabs were omitted. For any given size of pouch, that means that the provision of upwardly-projecting tabs reduces the effective volumetric capacity of the pouch. Also, the tab for a backing layer that extends upwardly away from the remainder of the faceplate may be exposed for possible contact with clothing and present the risk that such contact might initiate unintentional detachment of the faceplate from the skin.
It is therefore a main aspect of this invention to provide an ostomy appliance having an adhesive faceplate shaped and oriented to provide more effective adhesive attachment where it is needed most in resisting pulling forces in use, while reducing the area of adhesive attachment in the lower region of a faceplate where excessive contact might cause pinching and other patient discomforts. More specifically, the faceplate of the appliance is of inverted triangular shape having rounded corners, with one of the corners facing downwardly towards the lower end of the pouch and one of its side edges facing upwardly along the upper end of the pouch. The result is an appliance having a faceplate of greater width in its upper region (i.e., above the midpoint of its stoma-receiving opening) than in its lower region, thereby providing greater adhesion where it is needed most, reducing the size of the faceplate in its lower region to promote greater patient comfort, and also limiting material volume and expense (recognizing that hydrocolloid-containing adhesive compositions constitute a significant portion of the cost of such appliances).
Two of the rounded corners of the faceplate therefore face upwardly and outwardly and, in a preferred embodiment, both the removable release sheet and the backing layer of the symmetrical faceplate have non-protruding pull tabs along one of those corners. At such corner, the adhesive layer is set back or recessed to create a marginal corner area where the coextensive release sheet and backing layer, while following the regular marginal contour of the faceplate, have no adhesive material between them. Such adhesive-free portions therefore serve as pull tabs to facilitate removal of the release sheet at the time of application of the appliance as well as initiating detachment of the faceplate from the skin when removal is desired. Since the tabs are non-protruding--and especially because they are non-protruding in an upward direction--they do not interfere with close positioning of the faceplate to the upper margin of the pouch, thereby optimizing pouch volume. The fact that the tabs are non-protruding is also believed to reduce the possibility that movement of clothing or contact with other objects might initiate unintended detachment of the upper portion of the faceplate from the skin.
While the provision of such non-protruding tabs reduces the adhesive material that would otherwise be available for contact with the skin (or with the attachment surface of a mounting ring adhesively secured to the skin), the inverted triangular shape of the faceplate nevertheless assures that the adhesive surface in the upper region of the faceplate (i.e., above the midpoint of the faceplate opening) has greater width than in the faceplate's lower region and provides a substantial area of adhesion above and to the sides of the faceplate opening. Thus, the configuration and orientation of the faceplate optimize patient security while at the same time allowing for the provision of pull tabs along a portion of the upper margin of such a faceplate.
Other features, objects and advantages of the invention will become apparent from the specification and drawings.